In regards to:
- The end tag specifier must follow the << without any intermediate space.
- The actual end tag must be exactly the same as specified in the introduction line.
- The introduction line must end with a semicolon.
only the middle is correct. The only time the tag specifier must immediately follow the
<< is when it isn't quoted. That is,
<< "FOO" is ok whereas
<< FOO is not. And as for the semicolon, the truth of that matter is that the
<< "XXX" is merely a placeholder for a quoted string and the rest of the expression its in must continue to flow naturally.